Doutorado em Ecologia e Evolução (ICB)

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http://200.137.215.59/tede/handle/tde/203

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A Teoria Neutra pode explicar a diversidade de insetos aquáticos em riachos?
(Universidade Federal de Goiás, 2009-04-07) ALMEIDA, Mirian Cristina de; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648
The generality of Unified Neutral Theory of Biodiversity and Biogeography was evaluated across its support for diversity structure of Odonata adults and predators, shredders and collectors insect guilds in streams. The evaluation of Neutral Theory was done in two levels of theory s hierarchical structure. One evaluation in the level of yours assumptions, the zero sum assumption, and other in the level of yours predictions to abundance models in communities and metacommunities, ZSM and logseries respectively. The variations predicted to ZSM abundance model, in accordance to dispersal limitation that community are subjected, was evaluated in insect guilds through the streams distance. In Odonata adults the dispersal limitation was evaluated indirectly through regional frequency of species body size. In this case, the ecological equivalence was restricted for body size guilds. Communities of Zygoptera adults have low density and richness within streams. Individuals distribution was grouped, not consistent to linear relation under zero sum assumption. Local abundance of Odonata adults and predators, shredders and collectors guilds didn t fit ZSM model. Geometric series models and logseries models were better in explain the abundance for all groups. Moreover, the occurrence of fit to these models isn t in according to dispersal limitation level that is expected in each region, not supporting the Neutral predictions
Análise da comunidade de peixes e da teia trófica de um trecho do rio corrente - go
(Universidade Federal de Goiás, 2006-07-18) ALOÍSIO, Gustavo Ribeiro; ANGELINI, Ronaldo; http://lattes.cnpq.br/6739463859587165
In this work, fishes of Corrente river, affluent of Paranaíba River (Paraná basin, Brazil), were studied. Five surveys in the period of June of 2003 had been carried out until June of 2005. The sampling was executed in 8 points distributed in the stream, riverbed and lagoon. In each point had been used a set of gillnets with different mesh size (between 12 and 60mm opposite knots). The nets were inspected in the morning and the end of the day. The results had shown that 8 species were captured and the most abundant specie is Astyanax altiparanae; Shannon-Wienner index demonstrated diversity low; Morisita index indicated that there are high similarity between river, stream and lagoons; all species reproduce in the rainy season with exception of the Brycon nattereri; it is demonstrated the existence of piscivores species, herbivores, insectivores and detritus feeders.
A dinâmica do fitoplâncton em uma várzea Amazônica variações sazonal e nictimeral (Várzea do Lago Grande de Curuai Pará, Brasil)
(Universidade Federal de Goiás, 2011-03-28) ALVES, Carla Patrícia Pereira; NOGUEIRA, Ina de Souza; http://lattes.cnpq.br/3877834258990173
The river-floodplain systems are environments submitted a lateral overflow of river channel due the rains and/or underground waters. They are controlled by the type of climate, morphology and local effects. The lowland lakes are also highly productive because of the rich sources of primary carbon. The sediments transport and suspended and dissolved matter are done by the rivers between the land and aquatic phases. These phases strongly influence nutrient cycling, primary and secondary production and decomposition. The phytoplankton dynamics in tropical floodplain lakes is as variable as the seasonal and isolation patterns of flooding. For this reason, the aims of this work were i) to assess the rotation influence of potamophase and limnophase upon the phytoplankton of the Curuai Lake (PA, Brazil) and about the connectivity between other lakes, and ii) to evaluate the phytoplankton dynamics in a nictemeral cycling related to changes in CO2 in water, and what phytoplankton groups which were most important in this process. The phytoplankton community and environmental variables of the floodplain lakes of the Curuai Lake were sampled in the potamophase and limnophase (2009) and in a nictemeral cycling (2010). The informations summarized were obtained through the principal component analysis (PCA), canonical correspondence analysis (CCA), redundancy analysis (RDA) and nonmetric multidimensional scaling (MDS). The community structure was different among the periods with greater richness, density and phytoplanktonic biovolume in limnophase. There was predominance of Cryptophyceae (mainly Cryptomonas brasiliensis Castro, Bicudo & Bicudo) in potamophase and Cyanophyceae [Dolichospermum circinalis (formerly Anabaena circinalis) (Rabenh. ex Bornet et Flah.) Wacklin et al.] in limnophase, both influenced by environmental variables. In addition, the high phytoplanktonic biomass was favored by the highs temperatures and also responsible by the CO2 depletion in water caused by photosynthesis, which is reflected for the high carbon content in phytoplankton organisms. Despite the entry of water in the floodplain that connects the lakes, these environmental were distinct in relation a phytoplankton composition and a limnological variables. The phytoplanktonic community in Curuai Lake showed daily variation of biovolume because of high temperature and light availability. The development of persistent cyanobacteria bloom, with species predominance of Dolichospermum genius [functional group H1, D. spiroides (formerly A. spiroides) (Klebahn) Wacklin et al.] and Microcystis protocystis Crow (functional group M) caused the CO2 depletion in lake surface layer during the period of increased photosynthesis. The cyanobacteria bloom occurred mainly due to the attributes of group, which became it expressive competitors in relation another microalgae ones.
Ecologia reprodutiva de Cardiopetalum calophyllum (Annonaceae) em fragmentos de Cerrado do Brasil Central
(Universidade Federal de Goiás, 2010-03-31) ELIAS, Marcos Antonio da Silva; FRANCESCHINELLI, Edivani Villaron; http://lattes.cnpq.br/8863732932277904
Habitat fragmentation is one of the main causes of environmental degradation and a great threat to world biodiversity. Fragmentation can disrupt pollination processes, affecting directly or indirectly pollinators and plants. In Brazil, the Cerrado Biome has lost most part of its vegetation cover in the last four decades, becoming a highly fragmented landscape with many small fragments, several medium-size and a few continuous areas of vegetation. Those remnants have high biological diversity with high level of endemism, but very little is known about the reproductive success of their species. Cardiopetalum calophyllum Schletdl. (Annonaceae) occurs in the Cerrado of Central Brazil, has dicogamy and is pollinated by small beetle called Lobiopa insularis. The reproductive success of C. calophyllum and the abundance of its pollinator were analyzed in fragment of different size from July 2009 to January 2010. The reproductive success was estimated using fruit and seed set rates. Flowers in anthesis were collected to quantify the pollinator abundance inside them. A positive correlation between reproductive success of C. calophyllum and the fragment size was found. However, no correlation was found between pollinator abundance and fragment size. The small fragments are more isolated than the larger ones. This can decrease the pollinator dispersion and gene flow among fragments, increasing inbreeding within population of small fragments. The abundance of Lobiopa insularis seems to be more related to its generalist habits than to the fragment size. In our study, the effect of fragment size and reproductive success of C. calophyllum was stronger in fragments smaller than 10 ha. However, fragment smaller than 20 ha also showed decrease in their productive success.
Estrutura de comunidades de macroinvertebrados em riachos: efeitos de diferentes condições de perturbação sobre os processos de colonização e recolonização de substratos
(Universidade Federal de Goiás, 2011-08-29) Holanda, Luis Fernando Rabelo; Godoy, Bruno Spacek; Oliveira, Leandro Gonçalves; http://lattes.cnpq.br/4995825091971711; Oliveira , Leandro Gonçalves; Roque, Fábio de Oliveira; Garro, Francisco Leonardo Tejerina
Disturbance events affect the colonization and re-colonization process of streams by benthic macroinvertebrates. The Intermediate Disturbance Theory predicts distinct community patterns resultant by disturbance, where we can found coexistence or species loss. Such patterns vary with intensity and frequency of disturbance plus species trait, which can provide resistance or resilience to the community. An experiment was carried out to test the immediate and during time effects of two intensities and three frequencies of disturbance on the benthic macroinvertebrates community at five Cerrado streams, at Goiás State, Brazil. We tested two hypothesis: 1) Disturbance affect the permanency probabilities of species on substrates along time, but it’s more likely for cylindrical body and high mobility groups of species than to hydrodynamic body and short life cycle species group; and 2) Disturbance events change the community composition of aquatic invertebrates, such a way that through time there’s a tendency of increasing similarity of community. The low intensity disturbance did not have an immediately effect on the occurrence probabilities of hydrodynamic body, large body or grabbing species group. However, increasing on disturbance intensity drove to a negative effect of all groups, except the Elmidae larvae with flattened body. Through time, we observed resilience of R-strategists groups, seeing that their permanency probabilities weren’t affected by disturbance intensity and frequency through time. Furthermore, high intensity disturbance caused an immediately effect on community composition between control and treatment differing the proportion off spatial turnover and nesting process, driving dissimilarities resultant from species loss. Nevertheless, there was no support for the increasing similarity resultant of replacement or species loss through time hypothesis. These results indicate that, despite of the distinguished immediate effect of disturbance, there’s a fast pattern of re-colonization of substrates, which results in non discrepant community structure pattern. The more likely effect of disturbance is a redistribution of individuals between the different habitats, generating unpredictability on detection of species by traditional methodologies.
Riqueza e composição de mariposas Arctiinae (Lepidoptera, Noctuidae) em diferentes formações vegetais em uma área de cerrado
(Universidade Federal de Goiás, 2012-05-17) Santos, Carolina Moreno dos; Ferro, Viviane Gianluppi; http://lattes.cnpq.br/4073294502295550; Ferro, Viviane Gianluppi; http://lattes.cnpq.br/4073294502295550; Vasconcelos, Heraldo Luiz de; Almeida Neto, Mário
The Cerrado Biome presents a mosaic of vegetation ranging from open areas with no shrub component (grassland) to areas with a high density of tall trees (forests formations). This mosaic of vegetation that occurs in the Cerrado harbors a high biodiversity of different groups of animals and enables to this biome presents high beta diversity in the region. However, data of species occurrence are lacking for most groups of animals, especially for the invertebrates. In this work, Arctiinae moths were sampled in different vegetation formations of the Cerrado. Arctiinae are one of the richest subfamilies of Lepidoptera. About 11.000 species were described in worldwide, 6.000 in the Neotropics, 1.400 in Brazil and 720 in the Cerrado. Most larvae of Arctiinae are polyphagous. In addition to eating the green angiosperm and gymnosperm tissues, their ranks include species that consume algae, lichens, liverworts and mosses. Despite being polyphagous, the most species of Arctiinae feed mainly on the plant species that provide secondary metabolities (mainly pyrrolizidine alkaloids) that offer to them chemical protection against natural enemies. Thus, variations in the host plant species composition reflect at least partially in the variations in the moths species composition. In the first chapter of this dissertation, the Arctiinae moth fauna was characterized in four vegetation formations (dirty grassland, closed grassland, cerrado sensu stricto and semideciduous forest). Moths species richness was significantly higher in vegetation formations more structurally complex. The moth species composition in semideciduous forest was significantly dissimilar from the others vegetation formations. There was a positive correlation between the moths similarity patterns and the plants similarity patterns. In the first chapter was also tested the premise that structurally simple habitats presents a higher intensity of predation because they available less quantity of refuges for prey. This premise was corroborated because the predation intensity on artificial caterpillars was twice higher in the dirty grassland than in the structurally complex vegetation. In the second chapter of this dissertation was tested which environmental variable best determines the variation in Arctiinae species richness and composition between the vegetation formations of the cerrado sensu lato (dirty grassland, closed grassland and cerrado sensu stricto). The trees richness was the most determinant of moths species richness. The moth species composition was influenced by the trees richness, followed by herbs density, predation intensity and by the variation coefficient of tree height. The results that the vegetation characteristics are the best predictors of the variations in the moths species richness and composition indicate that it is necessary to invest in conservation measures of all vegetation formations that occurs in the Cerrado.

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